well, you have to be given an interval. That is not an interval.
You should be given something like [tex]1 \leq x \leq 2[/tex]
If you add those fractions up you'll just get a point on the number line.
Find the LCD for all of them which is 9/6 - 4/6 + 3/6 = 8/6 = 2/3
You'll end up with a point on 2/3
